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# ASAuthorizationPublicKeyCredentialLargeBlobRegistrationInput

A type that encapsulates input for large binary object extensions during registration.

```
struct ASAuthorizationPublicKeyCredentialLargeBlobRegistrationInput
```

## Overview

Use this type during registration of a new passkey to indicate whether the app
requires `largeBlob` support or just needs to know if it’s available.
This can be different per passkey, depending on which passkey provider someone chooses to use, but can’t change after you create the passkey.
This behavior mirrors the options available in the WebAuthn spec.

## Topics

### Determining binary large object support

[`supportRequirement`](/documentation/AuthenticationServices/ASAuthorizationPublicKeyCredentialLargeBlobRegistrationInput-swift.struct/supportRequirement-swift.property)

A type that represents the level of support required for the large binary object passkey extension.

[`ASAuthorizationPublicKeyCredentialLargeBlobRegistrationInput.SupportRequirement`](/documentation/AuthenticationServices/ASAuthorizationPublicKeyCredentialLargeBlobRegistrationInput-swift.struct/SupportRequirement-swift.enum)

Values that express the level of support required for the binary large object passkey extension.

### Using defined support values

[`supportPreferred`](/documentation/AuthenticationServices/ASAuthorizationPublicKeyCredentialLargeBlobRegistrationInput-swift.struct/supportPreferred)

A value that indicates the app needs binary large object support.

[`supportRequired`](/documentation/AuthenticationServices/ASAuthorizationPublicKeyCredentialLargeBlobRegistrationInput-swift.struct/supportRequired)

A value that indicates the app requires large binary object support.


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